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An Extension Study of HGT-HIT-045 Evaluating Long-Term Safety and Clinical Outcomes of Idursulfase-IT in Conjunction With Elaprase in Pediatric Participants With Hunter Syndrome and Cognitive Impairment

Phase 1
Completed
Conditions
Hunter Syndrome
Interventions
Drug: Idursulfase-IT
Registration Number
NCT01506141
Lead Sponsor
Takeda
Brief Summary

This extension study of HGT-HIT-045 is designed to collect long-term safety data in pediatric participants with Hunter syndrome and cognitive impairment who are receiving intrathecal (IT) idursulfase-IT and intravenous (IV) Elaprase enzyme replacement therapy.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
15
Inclusion Criteria
  • Participant must have completed all study requirements and End of study (EOS) assessments for study HGT-HIT-045 (NCT00920647) prior to enrolling in Study HGT-HIT-046 and must have no safety or medical issues that contraindicate participation.
  • The participant's parent(s) or legally authorized guardian(s) must have voluntarily signed an Institutional Review Board (IRB)/Independent Ethics Committee (IEC)-approved informed consent form after all relevant aspects of the study have been explained and discussed. Consent of the participant's parent(s) or legally authorized guardian(s) and the participant's assent, as relevant, must be obtained.
  • The participant has received and tolerated a minimum of 12 months of treatment with weekly IV infusions of Elaprase and has received 80% of the total planned infusions within the last 6 months.
Exclusion Criteria
  • The participant is enrolled in another clinical study that involves clinical investigations or use of any investigational product (drug or device) other than the PORT-A-CATH IDDD within 30 days prior to study enrollment or at any time during the study.

  • The participant is unable to comply with the protocol (eg, is unable to return for safety evaluations, or is otherwise unlikely to complete the study) as determined by the investigator.

  • The participant has experienced an adverse reaction to study drug in Study HGT-HIT-045 (NCT00920647) that contraindicates further treatment with intrathecal idursulfase-IT.

  • The participant has a known hypersensitivity to any of the components of idursulfase-IT.

  • The participant has any known or suspected hypersensitivity to anesthesia or is thought to be at an unacceptably high risk for anesthesia due to airway compromise or other conditions.

  • The participant has a condition that is contraindicated as described in the SOPH-A-PORT Mini S IDDD Instructions for Use, including:

    1. The participant has had, or may have, an allergic reaction to the materials of construction of the SOPH-A-PORT Mini S device

    2. The participant's body size is too small to support the size of the SOPH-A-PORT Mini S Access Port, as judged by the investigator

    3. The participant's drug therapy requires substances known to be incompatible with the materials of construction

    4. The participant has a known or suspected local or general infection

    5. The participant is at risk of abnormal bleeding due to a medical condition or therapy

    6. The participant has one or more spinal abnormalities that could complicate safe implantation or fixation

    7. The participant has a functioning CSF shunt device

    8. The participant has shown an intolerance to an implanted device

      An additional exclusion criterion for patients who were previously untreated with intrathecal idursulfase-IT in Study HGT-HIT-045 (NCT00920647):

  • The participant has an opening CSF pressure upon lumbar puncture that exceeds 30.0 centimeter (cm) water (H2O).

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Idursulfase-IT 1 milligram (mg)Idursulfase-ITParticipants will receive 1 mg idursulfase-IT intrathecally via intrathecal drug delivery device (IDDD) or lumbar puncture (LP) once monthly and standard-of-care (SoC) therapy of Elaprase intravenous (IV) infusions.
Idursulfase-IT 1 milligram (mg)ElapraseParticipants will receive 1 mg idursulfase-IT intrathecally via intrathecal drug delivery device (IDDD) or lumbar puncture (LP) once monthly and standard-of-care (SoC) therapy of Elaprase intravenous (IV) infusions.
Idursulfase-IT 10 mgIdursulfase-ITParticipants will receive 10 mg idursulfase-IT intrathecally via IDDD or LP once monthly and SoC therapy of Elaprase IV infusions.
Idursulfase-IT 10 mgElapraseParticipants will receive 10 mg idursulfase-IT intrathecally via IDDD or LP once monthly and SoC therapy of Elaprase IV infusions.
Idursulfase-IT 30 mgIdursulfase-ITParticipants will receive 30 mg idursulfase-IT intrathecally via IDDD or LP once monthly and SoC therapy of Elaprase IV infusions.
Idursulfase-IT 30 mgElapraseParticipants will receive 30 mg idursulfase-IT intrathecally via IDDD or LP once monthly and SoC therapy of Elaprase IV infusions.
Primary Outcome Measures
NameTimeMethod
Number of Participants With Treatment-emergent Adverse Events (TEAEs)From start of study drug administration up to follow-up (up to 165 months)

An adverse event (AE) is any noxious, pathologic, or unintended change in anatomical, physiologic, or metabolic function as indicated by physical signs, symptoms, and/or laboratory changes occurring in any phase of a clinical trial, and whether or not considered study drug-related. TEAEs were defined as all AEs occurring on or after the first IDDD surgery date or first dose (whichever is earlier) for the participant (whether it is in this extension study or in HGT HIT-045 \[NCT00920647\]) and before the end of the study (EOS) visit (+30 days). For Idursulfase-IT 1 mg+10 mg arm the summary presented includes only the TEAEs that occurred while the participants were assigned to 10 mg.

Number of Participants With Clinically Significant Changes or Apparent Difference Across Treatment Groups in Laboratory ParametersFrom start of study drug administration up to follow-up (up to 165 months)

Number of participants with clinically significant changes in laboratory parameters (chemistry, hematology, urinalysis and CSF values) were collected.

Number of Participants With Clinically Significant Changes or Apparent Difference Across Treatment Groups in 12-lead Electrocardiogram (ECG) FindingsFrom start of study drug administration up to follow-up (up to 165 months)

Number of participants with clinically significant changes in 12-lead Electrocardiogram (ECG) findings (heart rate, PR interval, QRS interval, QT interval and the corrected QT interval) were collected.

CSF Chemistries: Change From Baseline in CSF Total Cell CountBaseline, Month 163
CSF Chemistries: Change From Baseline in CSF GlucoseBaseline, Month 163
CSF Chemistries: Change From Baseline in CSF ProteinBaseline, Month 163
Number of Participants With Anti-idursulfase Antibodies in CSFFrom start of study drug administration up to follow-up (up to 165 months)
Number of Participants With Anti-idursulfase Antibodies in SerumFrom start of study drug administration up to follow-up (up to 165 months)
Secondary Outcome Measures
NameTimeMethod
Area Under the Curve Extrapolated to Infinity (AUC0-infinity) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Area under the curve extrapolated to infinity, calculated using the observed value of the last non-zero concentration (AUC0-infinity) of idursulfase was assessed. Participants in 1 mg arm group were assessed for Pharmacokinetic (PK) analysis in the HGT-HIT-045 study.

Area Under the Curve From the Time of Dosing to the Last Measureable Concentration (AUC0-t) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study.

Maximum Observed Concentration (Cmax) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study.

Time of Maximum Observed Concentration (Tmax) of Idursulfase Administered in as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study.

Total Body Clearance for Extravascular Administration Divided by the Fraction of Dose Absorbed (Cl/F) of Idursulfase-IT Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study.

Volume of Distribution Associated With the Terminal Slope Following Extravascular Administration Divided by the Fraction of Dose Absorbed (Vz/F) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study.

First Order Rate Constant (Lambda z) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study.

Terminal Half-life (t1/2) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, at 1,2,3,4,6,8,12,24,30,36 hours (±1 hour) following IT injection on Day 2 of Weeks 3,23, for 1 mg arm group and on Day 2 of Weeks 3,23, Months 19,31,43,55,67,79 for 10 and 30 mg arm groups

Participants in 1 mg arm group were assessed for PK analysis in the HGT-HIT-045 study. T1/2 is calculated by dividing 0.693 by Lambda z. Here, 0.693 is the natural logarithm of 2 and Lambda z is the first order rate constant.

Total Body Clearance (CL) of Elaprase15 minutes prior to IV infusion, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 9, 11, and 24 hours during/after the IV infusion on Days 3-7 of Weeks 3 and 23
Observed Steady-state Volume of Distribution (Vss) of Elaprase15 minutes prior to IV infusion and at multiple timepoint (0.5, 1, 1.5, 2, 2.5, and 3 hours during the infusion; and at 3.5, 4, 5, 6, 7, 9, 11, and 24 hours) following IV infusion on Days 3-7 of Weeks 3 and 23
Volume of Distribution (Vz) of Elaprase15 minutes prior to IV infusion and at multiple timepoints (0.5, 1, 1.5, 2, 2.5, and 3 hours during the infusion; and at 3.5, 4, 5, 6, 7, 9, 11, and 24 hours) following IV infusion on Days 3-7 of Weeks 3 and 23

Volume of distribution associated with the terminal slope (Vz) of Elaprase was assessed.

Mean Residence Time Extrapolated to Infinity (MRT0-inf) of Elaprase15 minutes prior to IV infusion and at multiple timepoints (0.5, 1, 1.5, 2, 2.5, and 3 hours during the infusion; and at 3.5, 4, 5, 6, 7, 9, 11, and 24 hours) following IV infusion on Days 3-7 of Weeks 3 and 23
Change From Baseline in CSF BiomarkersBaseline, Months 7, 55, and 139

Change from baseline in CSF biomarkers glycosaminoglycan (GAG \[heparan sulfate (HS)/dermatan sulfate (DS)\]) was assessed.

Change From Baseline in Urinary Glycosaminoglycan (GAG)Baseline, Months 7, 55, and 163

mg GAG/mmol creatinine stands for milligrams of GAG per millimole of creatinine.

Trial Locations

Locations (9)

Ann & Robert H Lurie Childrens Hospital of Chicago

🇺🇸

Chicago, Illinois, United States

University of North Carolina at Chapel Hill

🇺🇸

Chapel Hill, North Carolina, United States

Legacy Emanuel Hospital

🇺🇸

Portland, Oregon, United States

Children's Hospital of Pittsburgh of UPMC

🇺🇸

Pittsburgh, Pennsylvania, United States

Vanderbilt Children's Hospital

🇺🇸

Nashville, Tennessee, United States

University of Utah Hospital

🇺🇸

Salt Lake City, Utah, United States

Seattle Children's Hospital

🇺🇸

Seattle, Washington, United States

British Columbia Children's Hospital

🇨🇦

Vancouver, British Columbia, Canada

Birmingham Children's Hospital

🇬🇧

Birmingham, United Kingdom

Ann & Robert H Lurie Childrens Hospital of Chicago
🇺🇸Chicago, Illinois, United States

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